Very numerous: all areas, especially Connacht. Ir. Mac Donnchadha from first name Donnchadh, brown warrior. Modern Donncha. A branch of the Mac Dermots in Connacht. There is a Scottish connection as Donncha = Duncan. SGG.

MacDonncha:

Quite numerous: Conamara etc. Ir. Lang. See Mac Donagh. One of the few Ir. Lang. names to re-assert itself in the telephone directory.